1. Field of the Invention
This invention relates to connectors, and more specifically to connectors capable of handling high electric current.
2. Background Information
Electronic cards and modules usually are plugged into a connector that may be located on a motherboard, backpanel, or other printed circuit board (PCB). The connector on the PCB must be able to handle the electric current that flows between the electronic module and the PCB through the connector pins. Certain electronic modules, e.g., power supplies and voltage regulator modules, produce excessively high amounts of current through the connector pins.
FIG. 1 shows a cross-sectional diagram of a currently used voltage regulator module (VRM) connector design. This VRM connector is a modified Industry Standard Architecture (ISA) connector. The cross-section includes two individual contacts 12. Each contact is stamped and formed with one mating interface. Each contact is cold stacked in housing 10 at a 0.1xe2x80x3 pitch. Contacts 12 must rely on the housing to hold themselves. When the connector is at high temperature, as a result of high current, the housing material will creep/soften and contacts 12 will lose the support from housing 10. This, combined with the contact material stress relaxation, causes the contact 12 spring loosing normal force, leading to contact interface failure. For this reason, the current carrying capability for this connector is limited to about 3.4 amps per contact. At a given form factor of less than 4xe2x80x3, the maximum current that the connector in FIG. 1 can handle is only about 80 amps.
FIG. 2 shows a tuning fork contact design that may be used in a connector. This contact may be used to overcome the problems of the contacts in FIG. 1. With a tuning fork contact, the housing no longer plays any role in generating the contact normal force and, therefore, a key failure mechanism is eliminated. The normal force from VR module insertion is self contained in the contact. However, because of the blanking process limitation in the manufacturing of a tuning fork contact, the contact material thickness must be relatively thin and the small contact cross-sectional area will limit the current carrying capability.
FIG. 3 shows a diagram of another currently used power connector. High current power connectors generally use wide, blade-like contacts, such as the one used in CrownEdge from Tyco-Elcon. The CrownEdge contacts are problematic in that the inductance is relatively high. Moreover, the cost is also relatively high because of the contact design and assembly (i.e., an extra part called the xe2x80x9ccontact holderxe2x80x9d is used in the connector).
Power delivery and management is perhaps the biggest challenge facing some corporations today. Certain server and workstation platforms use voltage regulator modules to supply power to central processing units (CPU). Currently, many voltage regulator connectors can only carry about 80 amperes of current and cannot be used for future designs which may require 100 amperes of current and above. Therefore, there is a need for a connector with contacts for a voltage regulator module that may handle 100 amperes of current within a given specific form factor, and scalable to handle a much higher level.